The present disclosure relates to defect correcting technology carried out in a process of manufacturing a display device, and particularly to a defect correcting apparatus and a defect correcting method suitable for correcting a defect in a device pattern or a wiring pattern formed on a substrate such as a TFT (Thin Film Transistor) substrate of a FPD (flat panel display) or the like.
So-called flat panel displays such as organic EL (Electro Luminescence) displays, liquid crystal displays, and the like are now spread as display devices. These display devices are formed by a wiring substrate including elements such as a thin film transistor (TFT), a capacitor, and the like as well as various conductive members such as a plurality of pieces of wiring (for example signal wiring and potential supplying wiring) electrically coupled to these elements.
In the mass production of a wiring substrate forming such a display device, a so-called defect, such as a short circuit, which means that pieces of wiring or elements originally arranged so as to be separated from each other are electrically coupled to each other, a break, which means that internal parts of wiring or an element originally provided continuously are separated from each other, or the like, occurs due to the presence of foreign matter, for example. As the display device is increased in size, the occurrence of defects at the time of mass production increases defective parts occurring in the TFT substrate serving as a wiring substrate for driving the display device, and invites a decrease in yield. Thus, a defect correcting process for correcting (repairing) the defective parts may be essential.
Methods for correcting such defects as a short circuit, a break and the like include for example a method of cutting a short-circuit part by laser light irradiation (laser repair) and the connection of a break part by a laser CVD (Chemical Vapor Deposition) method.
For example, the present applicant has proposed a defect correcting method that divides a unit pixel (wiring section) on a substrate into a plurality of regions, selects an appropriate method for each region, and corrects defects (see Japanese Patent Laid-Open No. 2008-159930, hereinafter referred to as Patent Document 1).